- Anticancer prodrug studies: DielsAlder chemistry of 1-methylthio-1-(p- tolylsulfonyl)ethene
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The reactivity of 1-methylthio-1-(p-tolylsulfonyl)ethene (1) as a dienophile in DielsAlder chemistry is investigated. Cycloaddition reactions were carried out with a range of pyran-2-ones and isobenzofurans. The initial DielsAlder adducts have the potenti
- Pratt, Andrew J.,Rendle, Phillip M.,Steel, Peter J.
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experimental part
p. 945 - 950
(2012/08/27)
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- Heterocyclic synthesis by C-C bond formation. Thionium ion-mediated preparation of substituted pyrrolidines and piperidines
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Dithioacetal-S,S-dioxides 6 and 7 undergo cyclisation to give pyrrolidines and piperidines upon exposure to Lewis acid. An unexpected tandem cyclisation of 5 to give 10 is described.
- Craig, Donald,Meadows, James D.,Pecheux, Muriel
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p. 147 - 150
(2007/10/03)
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- Novel synthesis of γ-lactones starting from β,γ-unsaturated carboxylic esters
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A novel synthetic route to highly substituted γ-lactones was achieved by an intermolecular radical addition to 4-(methylthio)-4-(p-tolylsulfonyl)-3-butenoic ester (1) and its 2-(ethoxycarbonyl) derivative (2), which were easily prepared from (methylthio)methyl p-tolyl sulfone. Upon the irradiation of a solution of 1 and benzophenone in an alcohol (R1R2CHOH), the 1-hydroxyalkyl radical (R1R2C-OH) was generated and added regiospecifically to the 3-position of 1 to form an adduct that led to a γ-lactone by spontaneous intramolecular condensation. Similarly, 2 reacted with the alcohol to give α-(ethoxycarbonyl)-γ-lactones. The alcohol, which is a high boiling liquid or solid, can be employed in the form of a solution (10 molar amounts in acetonitrile) without greatly lowering the reaction efficiency.
- Kayano,Yajima,Akazome,Fujita,Ogura
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p. 3599 - 3609
(2007/10/03)
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- Donor substituted sulfonyl carbenes, 2: Organothio sulfonyl carbenes
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Organothio sulfonyl carbenes 3 have been generated via ylid thermolysis or via α-elimination starting from α-chloro α-organothio sulfones and their derivatives. They have been captured by suitable nucleophilic trapping reagents (diazomethane, enol ethers, and other). Their nucleophilic carbenoid precursors could be trapped by an electrophilic olefin (ketene dithioacetal S,S-dioxides as Michael acceptors). Stable carbene Z-dimers could be obtained under various conditions. Bromine catalyzed isomerization to E-isomers proved to be reversible.
- Schank, Kurt,Abdel Wahab, Aboel-Magd A.,Buegler, Stephan,Eigen, Peter,Jager, Juergen,Jost, Klaus
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p. 3721 - 3742
(2007/10/02)
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